The present invention relates to adjustable work table assemblies and, more particularly, to an adjustable work table assembly which is pivotally attached to a pair of wall mounted, vertically oriented support members. The work surface is further selectively vertically adjustable upon the support members.
The need and desirability of a multi-purpose, adjustable work table assembly whose various uses include a storage shelf, drafting table, or eating surface, for example, may be gathered from the variety of such structures presently available. These structures are typically wall mounted and offer a planar surface which may be moved in a continuously adjustable manner between a fully extended, horizontal position, and a fully retracted, vertical position with some people preferring the work surface to be tilted at an angle. When not in use, the work surface may be moved to the retracted, vertical position thereby giving more useful space to the room in which the work surface is located. Desirable features of these types of structures include stability and ease of adjustability.
One such structure may be seen in U.S. Pat. No. 4,791,873 issued to Towfigh on Dec. 20, 1988. The Towfigh patent discloses an adjustable work surface which is pivotally attached via linkages to a pair of vertical standards mounted to a wall. The vertical standards include a rear wall 18, a pair of side walls 20 and a pair of inwardly extending flanges 22, the inner edges of which define a longitudinally extending slot. Upper and lower linkages are provided with the upper linkages being directly attached to the bottom surface of the work surface, with first ends of each pair of the upper and lower linkages attached together at a common pivot 38. The rear ends of the linkages pivotally attach to respective yokes which are slidably engaged within the longitudinal channel of the respective standard. The yokes may be secured in the desired, vertical position with set screws 54 and 60 on the bottom and top yokes, respectively. Additionally, downward movement of the work surface is limited by a stop formed by a shoulder 62 in the lower linkage against which the top linkage rests when in the horizontal position.
While the Towfigh desk-top is similar in function to the present invention, it does not provide for adjustability of the position of the front end of the lower linkage to the upper linkage. This feature, as provided in the present invention, allows adjustability of the point of support for the work surface which may need to be changed according to the weight and position of a load placed upon the work surface. Furthermore, it is believed that the set screws of Towfigh do not provide adequate securement of the yokes within the standards and may fail to support the work surface under a heavy load. Lastly, the lower set screws require a separate tool to loosen and tighten, and all set screws require strength from the individual, thereby posing a difficulty for a disabled person.
Other types of adjustable folding work surfaces may be seen in the following U.S. patents:
No. 4,998,484 issued to Groetzinger on Mar. 12, 1991 which shows a slide slot 52 formed in the slide channel 50 through which a rod 70 extends movement of the upper support channel 40 therein. Adjustable bracket means are shown in FIG. 8 thereof.
No. 4,605,131 issued to Debus et al on Aug. 12, 1986.
No. 624,115 issued to Steele on May 2, 1899.
No. 3,026,158 issued to Freeman on March 20, 1962.